Piano-hammer molding and gluing machine.



M. GARDNER.

PIANO HAMMER MOLDING AND GLUING MACHINE.

APPLIOATION FILED SEPT. 6, 1910. 1,022,36 1 Patented Apr. 2, 1912.

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, M. GARDNER. PIANO HAMMER MOLDING AND GLUING MACHINE.

APPLICATION FILED SEPT. 6,1910.

Patented Apr. 2, 1912.

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M. GARDNER.

PIANO HAMMER MOLDING AND GLUING MACHINE.

APPLICATION FILED SEPT. 6, 1910.

Patented Apr. 2, 1912.

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COLUMBIA PLANOCIRAPH c UNITED STATES PATENT OFFICE.

MARTIN GARDNER, 0F DOLGEVILLE, CALIFORNIA.

PIANO-HAMMER MOLDING AND GLUING MACHINE.

To all whom it may concern:

Be it known that I, MARTIN GARDNER, a citizen of the United States, residing at Dolgeville, in the county of Los Angeles and State of California, have invented a new and useful Piano-Hammer Molding and Gluing Machine, of which the following is a specification.

This invention relates to means for gluing the felts on piano hammer moldings.

Objects of the invention are to produce uniform piano hammers at minimum expense of time and labor and with maximum ease, convenience and comfort to the op erator.

The invention embraces a piano hammer molding and gluing machine comprising a press provided with detachable bed-irons having adjustable caul holders in which the sets of hammer heads may be separably molded, glued and locked, and then removed from the press and put into a drying kiln so that the workman can operate in a room of normal temperature without being subjected to the extreme heat of 95 which is necessary to the gluing operation.

The invention is pioneer in this respect and it also includes other novel features of construction.

The novel elements and parts are particularly described and claimed in the subjoined detailed description.

The accompanying drawings illustrate the invention.

Figure 1 is a side elevation partly in section of a machine constructed in accordance with this invention, the parts being shown in the pressing position and one of the standards being in vertical mid-section. Fig. 2 is a cross-sectional elevation on line m m Figs. 1, 3, 11, 16 and 17. Fig. 3 is a reduced plan of the cauls and mechanism for operating and holding the same. The View is from the plane of line w-a;, Figs. 1, 2, 4 and 16, omitting the tray beam and its appurtenances. F ig. 1 is an enlarged fragmental sectional elevation on line w m Figs. 1, 3, 11, 16 and 17 showing the molding and gluing mechanism includ ing the bed-iron and omitting some of the connecting parts shown in other views. The parts are shown in solid lines in the position they occupy after the felt has been molded and before the moldings have been released. Dotted lines indicate the positions to which the various parts are moved Specification of Letters Patent.

Application filed September 6, 1910.

Patented Apr. 2, 1912.

Serial No. 580,743.

in the operation of releasing the bed-iron so that it and the set of hammers may be placed in the drying kiln. Fig. 4 is a view of the parts ready for the kiln. Figs. 5, 6, 7, 8, 9 and 10 are diagrammatic views to show various positions the parts occupy at different stages of the operation of the machine. The several positions shown in the diagrammatic views are designated in the several views by the characters, A, B, C, D, E and F. Fig. 11 is a fragmental plan view of parts of the machine from line a' a: Figs. 1, 2, 1 and 16, viewed from the same side as Fig. 1 and from the left side of Fig. 2. Fig. 11 is a cross sectional elevation on line 92 Fig. 11. Fig. 12 is a fragmental sectional detail from line in, Figs. 11 and 15, showing the tray fixed to the tray beam. Fig. 13 is a fragmental. sectional detail on line m Figs. 11 and 15, showing the tray beam without the tray. Fig. 14 is a fragmental sectional elevation on line 00 Fig. 11. Fig. 15 is a fragmental elevation from the farther side of Figs. 1 and 11 and the right side of Fig. 2. Fig. 16 is a fragmental longitudinal mid-sectional elevation on line m Figs. 2, 3, 4 and 11. F lg. 17 is a plan view of the bediron detached. Fig. 18 is a plan view of the felt-strip for a set of hammers before molding. Figs. 19 and 20 are elevations of the ends of the felt-strip. Fig. 21 is a plan of a mold. Figs. 22 and 23 are elevations of the ends of the mold.

Arrows in the several views indicate the direction of sight.

The frame comprises complementary end standards 1, 2, and top and middle beams 3, t. The standards may be of cast iron and the beams may be of hollow iron castings bolted to the standards at the top and the middle by one inch cap screws 5 screwed through the top and middle cross webs 6, 7, of the standards and into the ends of the beams. The joints between the middle beam 4. and middle webs 7 are strengthened by dowels S. The frame is also provided at the bottom with a guide beam 9 fastened to the bottom webs 10 by cap screws 11. The middle. beam 1 is provided with a longitudinal way 12 which extends lengthwise of the frame to receive the bed-iron 13 which is carried by the middle beam 4.

The bed-iron 13 may be of cast-iron or other suitable material and is provided with a mold channel 14 and base and top flanges 15 and 16 which are connected by the central web 17 that forms the bottom of the mold channel 14, that is of uniform depth from end to end and tapers in width from one end to the other to receive the longitudinal tapering wooden hammer mold 18. The mold channel 14 and the hammer mold 18 are practically the same as they occur in the old style hand piano hammer presses.

The top faces of the bed-iron flanges 16 and of the mold 18 are flush with each other thus forming a continuous smooth surface to receive a strip of molding covering 19 such as is generally employed, consisting of felt cut to triangular cross-section and decreasing in thickness and width from end to end as shown in Figs. 18, 19 and 20.

Vertical and bi-lateral pressure mecha nisms operated by piston means are pro vided to mold and glue the covering to a set of hammer moldings, the vertical pressure mechanism forcing the covering into the mold and holding it there, and the lateral pressure mechanism molding and gluing the outer port-ions of the covering to the moldings.

The vertical pressure mechanism comprises a cleft tray which is arranged above the middle of the mold 18 and is composed of two members 20, 21, and has a slot 22 from end to end of sufficient depth to receive the heads 23 of the hammer moldings 24; one half of the slot being in one member and the other half in the other member. The bottom of the slot is curved to conform with the ends of the moldings placed therein. The tray members 20, 21 are held together by stud bolts 25 to lock the moldings in the usual way. The slot 22 is provided in its bottom with the usual filler 26 along a portion of its length, approximately a fourth, to decrease the depth of the slot at such portion in conformity with the shorter moldings of the set that form base hammers in a piano; said filler being curved on its top and bottom to conform with the curvature of the slot bottom.

The tray is contacted on one side and top by the angular faces 27, 28 of a recessed tray beam 29; the face 27 being vertical and the face 28 being horizontal and overhanging the tray and having a plurality of slots 30 that are wider at the top than bottom, the back edges of which are vertical and the distance between said back edges and the vertical face 27 being less than the thickness of the tray.

Each slot is provided with a wedge 31 to fit and slide up and down in the slot, each wedge being longer than its slot, so that when the wedge is down in and fills its slot the projecting lower end of the wedge will contact with the outer face 32 of the tray and so hold the tray against the vertical face 27 of the tray-beam; and when the wedge 31 is up in the slot 30 the lower end will be drawn within the slot thereby releasing the tray from the wedging effect.

Each of the wedges 31 is provided with a shouldered screw 33 screwed therein and projecting through a slot 34 in the tray beam; the slot being of sufficient length to admit of the necessary vertical movement of the screws to secure the wedging and releasing effects and said shouldered screws extending through diagonal slots 35 in a shifter bar 36 which is a flat bar resting against a vertical face 37 of the tray-beam, and held in longitudinal alinement by shouldered screws 38 entered through slots 39 in the bar 36 and screwed into the traybeam. Said slots 39 are central in the bar 36 and hold said bar from up and down movement, but are sufficiently long to allow of longitudinal movement for the purpose of shifting the shouldered screws 33 from one end of the diagonal slot to the other end thus to move the wedges up as the bar is shifted endwise in one direction and down as it is shifted in the other direction.

The shifter bar 36 is provided on its outer face with a bracket 40 fastened thereto by cap screws 41; said bracket being provided with a fulcrum stud 42 having a head 43 on one end and a nut 44 on the other end to pivotally hold one end of a link 45, the other end of which link is provided with a fork 46 to receive a shifter-lever 47 which is pivoted to the link by a stud 48 that is provided on one end with a head 49 and on the other end with a nut 50. Said shifter-lever is provided at one end with a handle 51 and the other end is pivotally connected by a stud 52 to a bracket 53 fixed by cap screws 54 to the vertical face of the tray-beam 29; said stud having a head 55 on one end and a nut 56 on the other end to hold the stud 52 in place.

When the lever handle 51 is shifted to the left in Figs. 1 and '11, the shouldered screws 33 fixed in the wedges 31 are at the bottom of the diagonal slots 35 and hence hold the wedges against the face 32 of the tray; and when the lever handle is shifted to the right the shouldered screws are moved to the top of the diagonal slots, thus raising the wedges to the dotted position in Fig. 14 and dis engaging their ends from the face 32 of the tray.

The tray beam is provided on its under face with a pair of brackets 57 fixed thereto by cap screws 58 passed through one end of their horizontal limbs, the other ends of which limbs have vertical members 59 that extend upward and are provided with holes 60 adapted to guide and support the outer ends of cylindrical latch pins 61 the other ends of which pass through and are supported by holes 62, in the lower part of the tray beam and through holes 63 in the tray,

about central vertically thereof and just above the slot 22 for the hammer moldings.

The latchpins are provided intermediately with shoulders 64, 65, adapted to be engaged by the forks 06 of the latch shifters 67 which are keyed to a rock-shaft (38 that is provided at its ends with journals 09 fixed by cap screws 70 to the -vertical face 71 of the tray beam 29. One of the latch shifters 07 is provided above the ournal (39 with an extension '72 provided with a fork 73 to receive one end of a latch shifter bar 7 1, to which it is pivoted by a bolt 75. The latch shifter bar 74 is practically rectangular, being provided at its outer end with a slotted handle 76 and when pulled rotates the rock-shaft G8 and its latch shifters 07 to cause the forks to shift the latch pins 61 backward through the holes in the tray beam and tray, thus disengaging them from the tray and disconnecting the moldingmoving means from the molding-locking means; and when the handle is pushed back rotates the rock shaft (38 and its latch shifters 07 in a reverse direction to cause the forks to shift the latch pins 01 forward through the holes in the tray-beam and tray, thus locking the tray against separation from the tray-beam in a downward direction.

The tray-beam 29 extends from end to end of the machine to the outer edges of the standards 1, 2, each end being engaged by a pair of flat guides 77, 78, one on either side of the tray-beam. Said guides are of the width of the standards, are strengthened by triangular-shaped webs 7 9, and have flanged bases 80, which are fixed by cap screws 81. beneath the top beam 3 to steady and guide the tray-beam while operating. The tray beam is provided with a longitudinal slot 82 extending from end to end adapted to receive the ends of a plurality of piston rods 83, said ends being flattened on the contacting sides and fixed by pins 8 1 to the traybeam 29; said piston rods being provided for suspending and transmitting motion to the tray-beam and its appurtenances. Each piston rod 83 extends upward through the top beam 3 and is provided with a shoulder 85 against which a piston head 80 of usual construction is fixed by a nut 87 threaded on the piston rod. Each piston head'is contained in a cylinder 88 fixed on the top beam 3 by cap screws 89, the beam forming one end wall of the cylinder bore which is closed at the other end by a. head 90 fixed to the cylinder by stud bolts.

Each piston rod has an extension 91 which passes upward through the head and is provided on its upper end with a spring-seat 92 fixed by a pin 93. Surrounding the upper end of each piston rod extension is a helical spring 94 seated between the spring-seat 92 and cylinder-head 90, and adapted to normally hold the pistons up to suspend the traybeam and its appurtenances free from the mold. Each of the springs is contained in a spring chamber 95 closed at the upper end by a screw cap 90 and threaded at the lower end into a flange 97 fixed by cap screws on the upper surface of the cylinder head.

Openings 98 are provided in the cylinderheads into each of which is screwed a nipple 99 of the distributing pipe 100 that extends to one end of the machine and there downward to a three-way cock 101 that admits and controls compressed air from the supply pipe a and also exhausts the same from the distributing pipe during and after the operation of molding and gluing.

The centering and bi-lateral pressure mechanism con'i 'irises oppositely arranged cauls 102 that are of the ordinary construction well-known in the art, being provided with inner faces that overhang the mold to give the appropriate form to the hammers, and angular outer faces to engage the corresponding angular faces 103 of caul-holders 104 that are fixed to the cauls by cap screws.

The opposite sides of the bed-iron .13 are provided in its edges of the top flange 10 with vertical slots 105 to accommodate bolts 106 which pass through the eaul-holders for the purpose of guiding them and locking them to the bed-iron when it is desired to place the work in the kiln.

The bed-iron, mold, cauls and caul-holders are preferably long enough to mold a full set of piano hammers at one time and the outer faces of the caul-holdcrs are parallel with each other and with the longitudinal axis of the machine and are convex to contact with the corresponding inner concave faces of clamps 107, that are otherwise rectangular bars of the same length as the caulholders.

Each clamp is fastened at its outer edge by rivets 108 to a plurality of clamp holders 109 that are rectangular blocks, provided with slots 110 in their inner ends to engage the outer edges of the clamps. The clampholders are pivotally connected at their outer ends by pins 111 to levers 112 by which the clamp-holders are horizontally movable. Each lever is composed of two parallel flat bars having a fulcrum pin 113 intermediately in the upper half thereof extending through bolt bars and passing through a pair of flanges 11.41 of a bracket 11:") fixed by cap screws 115 to the side of the middle beam 41, said fulcrum pins being fastened at both ends with cotter pins 115" so that the lever bars 112 may be removed independently.

The levers 112 are each provided with stops 110 that may be pins passing through the levers just beneath the clamp-holders, and having their ends fixed in the lGYQP- &

bars for the purpose of preventing the clamps from dropping below the top flange of the bed-iron when not in contact therewith.

The lever bars composing each lever are pivotally and adjustably connected at their lower ends by a pivot block 117, a connectmg rod 118 and two adjusting nuts 119, 120 with a cross head 121 that is operated by the shouldered caul-operating piston rod 122. By means of the nuts an accurate adjustment may be made in order to exactly center the covering when the caul-operating piston rods 122 make their down stroke to simultaneously move the cauls toward each other.

The connecting rods 118 are connected in opposite pairs by pins 123 to the crosshead 121 and the cross-head is fixed by a pin 124 to the vertical piston rod 122, the lower end of which passes through the guidebeam 9 that holds it against radial movement. The upper ends of the rods 122 are provided with shoulders against which the lower piston heads 125 are held by nuts 126 threaded on the ends of said piston rods. The levers, connecting rods and cross heads thus provide leverage means exerting pressure that varies directly as the resistance to transmit pressure to the molding means.

The piston heads 125 operate in cylinders 127 that are fastened by cap screws beneath the middle beam 1 which forms the upper end wall of the cylinder bore, the other end of which bore is closed by a cylinder head 128 that is fastened to the cylinder by stud bolts.

The pivots 129 of the blocks 117 project beyond the outer faces of the lever bars sufficiently to hold the ends of the helical retracting springs 130, the other ends of which springs are fastened by eye bolts 131 to the cylinder heads 128 to normally hold the lower ends of the levers inward and the cant-holder clamps out of engagement with and away from the caul-holders and bediron; thus disconnecting the caul-moving means from the caul-holding locking means.

Compressed air is admitted to the lower cylinder at the upper end thereof above the piston headsthrough nipples 132 screwed into ports 133 in the walls of the cylinders and connecting them to a distributing pipe 134! that leads to one end of the machine and upward along one side of the standard 2 to a three-way cock 135 by which the oom pressed air is admitted from the supply pipe a and exhausted from the distributing pipe.

To make a setof piano hammers the operator will place a set of moldings in a tray 20, 21, looking them by the stud bolts 25 and will then place the tray in the traybeam with the latch-pins 61 projecting therethrough. Then he will move the lever 47 to shift the shifter bar 86 endwise to bind the wedges 31 endwise against the tray, thus firmly locking the tray to the tray-beam.

A bed-iron containing a mold is thereupon slid in the way 12, and a previously cut cover strip 19 is placed about centrally on the mold; then air is admitted to the lower cylinders to move the cauls, toward the covering to center it on the mold, as shown at A, Fig. 5; and then the air is shut 0E. Then air is admitted to the top cylinders to move the tray downward to cause the tips of the hammer moldings to touch the center of the covering and hold it in place on the mold. Then air is exhausted from the lower cylinders to allow the springs 130 to retract the cauls. Then an adhesiveagent, as glue, is applied to the covering on both sides of the moldings. More compressed air is then admitted to the top cylinders to force the moldings and the coverings thereon down into the mold as shown at B. Compressed air is then admitted to the bottom cylinders to force the cauls against the moldings as shown at C. More compressed air is then admitted to the top cylinders to stretch the outer face of the covering and force the covering more compactly into the mold.

WVhile the full pressure is maintained the cauls and their holders are locked to the bed iron by screwing up the nuts on the bolts 106; the wedges are retracted by reversing the lever 4-7 and the latch pins are withdrawn from the tray by pulling the handle 74-, thus unlocking the tray from the tray beam as shown at D; after which the threeway cocks are operated to relieve the air pressure in all of the cylinders and the springs retract the tray beam and caul holder clamps, as shown at E; whereupon the bed-iron and the parts locked thereto as shown in Fig. 1 are removed from the machine to the drying kiln, the pressure mechanism assuming the positions shown at F, Fig. 10.

It is thus seen that I have provided in this piano hammer molding and gluing machine, an organization comprising molding means, levers to operate the molding means, connecting rods pivoted to the levers, a crosshead pivoted to the connecting rods and arranged in such relation to the levers that the pressure increases toward the end of their movement, at which time the resistance of the compressed felt increases, and means to adjust the relation of the connecting rods to suit the varying conditions of different materials to be compressed, thus giving the machine a practically universal application to the purpose set forth.

Another bed-iron, mold, cauls, caul-holders, tray containing a new. set of hammer moldings and a new covering are then substituted for those removed and the operations described repeated ad infinitum, the number of such removable parts being sufliciently great to insure continuous operation.

It is understood that the pistons may be operated by liquid or gaseous medium as preferred by the constructor without chang ing the principal of the apparatus.

I claim 1. In a piano hammer molding and gluing machine the combination with oppositely arranged cauls, of caul-holders fixed to the cauls, clamps adapted to contact the caulholders, clamp-holders fixed to the clamps, oppositely arranged adjusting means, levers pivoted at one of their ends to the clampholders, and at their other ends to the adjusting means, cross-heads each pivoted to a pair of said adjusting means and piston means to operate the cross-heads.

2. In a piano hammer molding and gluing machine the combination with a removable tray and means to operate the tray, of wedge and latch means to lock the tray to the tray-operating means.

3. A piano hammer molding and gluing machine comprising a mold adapted to receive a strip of hammer molding covering, a tray above the mold to hold a set of piano hammermoldings, means to lock the hammer moldings in the tray, means to move the moldings toward the covering and force the center portion thereof into the mold, means to lock the molding-moving means to the molding locking means cauls above the mold, means to hold the cauls, means to move the cauls toward the moldings and force the outer portions of the covering thereagainst, means to lock the caul-holding means, and means to retract the caul moving means from the caul-holding locking means.

4. A piano hammer molding and gluing machine comprising a frame; a removable bed-iron on the frame; a mold seated in the bed-iron and adapted to receive a strip of hammer molding covering; a tray above the mold to hold a set of piano hammer moldings; means to lock the hammer-moldings in the tray; means to move the moldings toward the covering and force the center portion thereof into the mold channel; means to lock the molding-means to the molding locking means cauls above the bediron; means to hold the cauls; means to move the cauls toward the hammer-moldings to force the outer portions of the covering thereagainst; means to lock the caul-holding means to the bed-iron; means to retract the molding-moving means; and means to retract the caul-moving means from the means that look the caul-holding means.

5. In a piano hammer molding and gluing machine the combination with a bediron, a mold and operatalole cauls adapted to mold the covering on hammer moldings, of molding-locking means and means to lock the mold, the molding-locking means and cauls against movement relative to the bediron.

6. In a piano hammer molding and gluing machine the combination with a mold tray and cauls, of means to lock the cauls and tray against movement relative to the mold.

7. A piano hammer molding and gluing machine comprising a frame; a bed-iron on the frame and removable therefrom; a mold seated in the bed-iron and adapted to receive the hammer-molding covering; a traybeam above the mold; a tray above the mold to hold a set of piano hammer moldings; means to lock the hammer moldings in the tray; means to temporarily connect the tray with the tray-beam; means to move the traybcam toward the mold to force the tips of the hammer moldings to contact the center portion of the covering thereby to force said portion into the mold channel; cauls above and slidable on the bed-iron; holders fastened to the cauls; means to guide the caulholders; clamps adapted to contact the caulholders; means to move the clamps toward the hammer-moldings to force the outer portion of the covering against the sides of the hammer moldings; means to lock the caul-holders and tray against movement relative to the mold; means to disconnect the tray from the tray-beam; means to retract the tray-beam while the tray is locked to the moldings; and means to retract the clamps from contact with the caul-holders while the caul-holders are locked.

S. A piano hammer molding and gluing machine comprising a frame; a bed-iron on the frame and removable therefrom; a mold seated in the bed-iron and adapted to receive the hammer-mo]ding covering; a tray-beam above the tray, there being a slot in the tray to hold a set of piano hammer moldings; a tray arranged above the mold; means to lock the hammer moldings in the slot; wedge and latch means to temporarily connect the tray with the tray-beam; rods fastened to the tray-heam to move it toward the mold to force the tips of the hammer-moldings to contact the center portion of the covering, thereby to force said portion into the mold channel; means to move the piston rods; cauls above and slidable on the bed-iron; holders fastened to the cauls; means to guide the caul-holders; clamps adapted to contact the caul-holders; lever means to move the clamps toward the hammer moldings to force the outer portions of the covering against the sides of the hammer moldings; means to move the levers; means to lock the caul-holding means against movement relative to the mold; means to operate the wedge and latch means to disconnect the tray from the tray-beam; piston-means to retract the tray-beam while the caul-holding means are locked; and piston operated lever means to retract the clamps from contact with the caul-holders while the caul-holding means are locked.

9. A piano hammer molding and gluing machine comprising a mold adapted to receive the hammer molding covering; atray to hold a set of hammer moldings; vertical pressure mechanism connected to the tray to move the moldings toward the covering to hold and partially mold the covering to the hammer moldings; cauls above the mold; holders fastened to the cauls; clamps contacting the caul-holders and disconnectible therefrom; loi-lateral pressure mechanism to move the clamps simultaneously toward the cauls to center the covering and to finish molding the covering to the moldings while so held; means to regulate the pressure of said mechanisms; wedges and latches to detachably connect the tray to the vertical pressure mechanism; means to operate the wedges; means to operate the latches; means to lock the tray and the caul-holders against movement relative to the mold and means to move the vertical and bi-lateral pressure mechanisms away from the tray and caulholders while locked.

10. A piano hammer molding and gluing machine comprising a mold adapted to receive the hammer molding covering; a tray to hold a set ofhammer moldings; a beam to detachaloly hold the tray; vertical pressure mechanism connected to the tray beam to move the moldings toward the covering to hold and partially mold the covering to the hammer moldings; cauls above the mold holders fastened to the cauls; clamps contacting the caul-holders and disconnectible therefrom; loi-lateral pressure mechanisms to move the clamps simultaneously toward the cauls to center the covering and to finish molding the coverings to the molding while so held; means to regulate the pressure, there being slots in the tray-beam; wedges in the slots adapted when moved in one direction to contact with the tray and hold it against the tray-beam and when moved in the opposite direction to be disengaged from the tray; means to shift the wedges; latch-pins adapted when moved in one direction to connect the tray-beam to the tray and when moved in the reverse direction to disconnect the tray-beam from the tray; means to shift the latch-pins; means to lock the tray and the caul-holder against movement relative to the mold, and means to move the vertical and bi-lateral pressure means away from the tray and canlholders while so locked.

11. A piano hammer molding and gluing machine comprising a mold adapted to receive the hammer molding covering; a tray to hold a set of hammer moldings; a beam to detachably hold the tray; vertical pressure mechanism connected to the tray-beam to move the moldings toward the covering to hold the covering and to partially mold the covering to the hammer moldings cauls above the mold; holders fastened to the cauls; clamps contacting the caul holders and disconnectible therefrom bi-lateral pressure mechanisms to move the clamps simultaneously toward the cauls to center the covering and to finish molding the covering to the moldings while so held means to regulate the pressure there being slots in the tray-beam; wedges in the slots adapted when moved in one direction to contact with the tray and hold it against the tray-beam and when moved in the opposite direction to be disengaged from the tray; screws fixed in the wedges and accommodated in slots in the tray-beam; a shifter-bar fastened to and slidable longitudinally on the traybeam and provided with diagonal slots to accommodate the outer ends of the screws; means to shift the bar; latch pins adapted when moved endwise in one direction to connect the tray-beam to the tray and when moved in the reverse direction to disconnect the tray-beam from the tray; shoulders on the latch pins; a shifter provided with a fork to contact the shoulders thereby to shift the pins endwise;

a rock-shaft connecting the shifters; means to rock the shaft; means to lock the tray and the caul-holder against movement relative to the mold and means to retract the vertical and bi-lateral pressure mechanisms from the tray and caul-holders so locked.

12. In a piano hammer molding and'gluing machine, the combination with a removable mold and pressure mechanism, of a tray to hold hammer moldings and means to detachably connect the tray with the pressure mechanism.

13. In a piano hammer molding and gluing machine, molding means, levers to operate the molding means, connecting rods pivoted to the levers, a cross-head pivoted to the connecting rods and arranged in such relation to the levers that the pressure increases toward the end of their movement, at which time the resistance of the com pressed felt increases, and means to adjust the relation of the connecting rods to suit the varying conditions of different materials to be compressed.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 31st day of August 1910.

MARTIN GARDNER.

In presence of- GEORGE H. HILES, OLIVE DIFFENDERFER, JAMns R. TOWNSEND.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

Washington, D. G. 

